Today's consumer automobiles utilize systems such as VCM (Variable Cylinder Management) to save fuel during specific driving conditions. Such techniques in Honda vehicles are referenced by U.S. Pat. No. 5,636,609A, and U.S. Pat. No. 7,836,866. Other automotive manufacturers have similar systems that effectively shut down a number of cylinders dynamically during operation. These systems were primarily invented to improve gas mileage performance in order to meet increasingly demanding EPA (Environment Protection Agency) regulations since the early 2000's. VCM/ECO mode is not an EPA standard, and is a manufacturer-specific in the case of Honda. GM uses a technology called AFM (Active Fuel Management) to accomplish cylinder de-activation. Dodge utilizes a technology called MDS (Multi-Displacement System) to accomplish cylinder de-activation. These VCM/ECO mode enhancements allow manufacturers to advertise unrealistic maximum MPG (Miles per Gallon) estimates for the sake of benchmarking, supposedly giving consumers a standard by which to select a vehicle for purchase. While these VCM/ECO systems (termed herein “variable cylinder management technology”) have facilitated an improved gas mileage on freeway, vehicles utilizing them see an improved 1-2 miles per gallon in very specific instances. In addition, the currently available variable cylinder management technologies have caused numerous maintenance problems for users. To name some, these systems have caused increase engine vibration and oil consumption, pre-mature wear of the cylinder rings and fouling of spark plugs. More specific examples are the 2008-2013 Honda Odyssey, Pilot, Accord vehicles with 3.5 L engines that utilize variable cylinder management (VCM), and have had class-action lawsuits from VCM-2 technology in certain model years. Vehicle owners have documented engine motor and torsion mount failures every 50-80 k miles, as well as and premature torque-converter transmission failures, resulting from the variable cylinder management technology. These problems have created an undue burden on users as they substantially increased the total cost of ownership of vehicles in which the variable cylinder management technology is implemented, mainly from poorly designed parts that wear out prematurely, as well as the constant engage/disengage of the VCM/ECO systems. Normally engine and torsion motor mounts would last some 100K+ miles or the lifetime of the vehicle without issues in non VCM vehicles such as the pre-2005 Honda vehicles.
With some vehicles the VCM/ECO features can be disabled through an odb2 scan tool, such as on GM vehicles. However, with some makes of vehicles, such as Honda vehicles, such features cannot be disabled without modified firmware from the manufacturer to date.
This present disclosure focuses on work-arounds (methods enclosed herein) that a user can apply to the vehicle such as, for example, changing the signals sent from specific sensors such as a primary or secondary temperature (ECT) and/or oil pressure sensors to fool the computer into disabling the VCM/ECO (or any variable cylinder management technology) like features, thus avoiding secondary problems for the vehicle. The methods of the present disclosure disable the variable cylinder management technology without issuing a check-engine light, and enable working in all climates. Normally, disabling these systems requires modifying the resistance of a particular sensor circuit, thus changing the voltage returned to a specific vehicle ECU sensor. However, different climates and temperatures under the hood make it difficult for a single resistance modification value to work in all scenarios.
Due to the difficulty of existing methods to disable the variable cylinder management technologies, many users have no other option but to leave a check-engine light on the vehicle and disabling some known sensors documented by manufacturer diagnostic troubleshooting manuals to turn these VCM/ECO (or any other variable cylinder management technology) features off. However, this creates an annoyance and may even invalidate warranties issued by manufacturers. For most vehicles, it is unlikely the automotive manufacturer will disable these features due to previously advertised EPA MPG (Miles Per gallon) standards, which might result in fines to the manufacturer.
Therefore, consumers are desperate to find ways to ‘hack’, or manipulate, the external feedback systems to the computer to disable these systems without triggering a check engine light. These manipulations may not be supported by the manufacturer and may void warranties, but beyond the 3 year, 36,000 mile standard warranty on a vehicle, the consumer is liable for the defects beyond the warranty period. A plug-and-play method to allow the consumer to enable/disable these features is necessary, especially where it can be added and removed within a matter of minutes when taking the vehicle in for regular maintenance.
As an example, some users discovered that VCM type features were disabled on some vehicles until they were completely warmed up to normal operating temperature and made plug-in harnesses that would reduce the reported temperature sent to the vehicle ECU to keep the temp (ECT) below a specific point and disable VCM/ECO using an inline resistor, which is wired in series with the ECT sensor. However, these technologies would not work in all climates and instances, due to factory variances with resistance in coolant temperature sensors, outside temperatures in warmer climates, vehicle sitting in traffic with the A/C on, and colder climates.
A solution is needed that would disable VCM in all scenarios without compromising the remaining systems that a user could easily adjust based on the seasons and conditions. The methods disclosed herein provide a much-needed solution to enable the vehicle user to decide on how to deal smartly and easily with their vehicle variable cylinder management technologies.